Red alert for blue-green algae downstream of Lake Brewster

Red alert for blue-green algae downstream of Lake Brewster

08 January 2021

A Red Alert level warning (high alert) for blue-green algae has been issued from Lake Brewster outlet in Mountain Creek and down the Lachlan River to Willandra Weir.

The alert follows information and some photos of green-coloured water received from the public. New algal samples from parts of the affected area were taken by WaterNSW field staff today and sent to the laboratory for analysis.

A Red Alert level warning indicates that people should not undertake recreational activities where they may be coming into direct contact with the water such as swimming, as well as domestic uses including showering and washing. Contact with the water may also pose a threat to livestock and pets.

Blue-green algae usually appear as green paint-like scums on the water, near the edges, or as greenish clumps throughout the water. It makes the water appear dirty, green or discoloured and generally has a strong musty or earthy odour.

Any water with a green tinge or a scum should be considered as being potentially toxic. Algae in such water may cause gastroenteritis in humans if consumed and skin and eye irritations after contact. Boiling the water does not remove algal toxins. Water users should also bear in mind that the algal affected water may spread downstream in the Lachlan River.

People are advised not to enter the water, drink untreated water or bathe in water drawn from the affected area while this Red Alert level warning is in place. Town water supplies remain unaffected and safe to drink.

Livestock owners are reminded to continue to check stock water supplies for blue-green algae and to remove stock from foreshores where surface scum is visible or blue-green algae are suspected.

People should not eat mussels or crayfish from Red Alert warning areas. Before consumption, any fish caught should be cleaned and washed thoroughly in uncontaminated water and any internal organs disposed of appropriately.

Blue-green algae occur naturally and can reproduce quickly in favourable conditions where there is still or slow-flowing water, abundant sunlight and sufficient levels of nutrients.

It is not possible to predict how long the algae will remain at high levels or where it may spread to. Regular monitoring will continue, and the alert will be lifted as soon as the high levels of algae dissipate.

People who believe they may have been affected by blue-green algae are advised to seek medical advice.

Updates and information about blue-green algae blooms and red level warning areas can be obtained by calling 1800 999 457 or visiting –

Media Contact – Tony Webber – 0428 613 478


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